Improvement in rotarv valves



2Sheets-Sheet1. J. F. SWEET.

ROTARY-VALVE.

Patented Feb. 1,1876.

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UNITED JOHN-F. Swen-0E1 onions: RArIDs,.IowA;. -I

I-VMPROVV'EM'EUINTMIN,RQTARVVALVES;

. 'Spec ification'forming m of Letters Patent No. 173,os 4, d t d February 1, 1876 application filed I l August 14,-1e75.u a I To all whom: it may concern:

Be it known that I, JOHN F. SWEET, -of

Cedar Rapids, in the :c'ounty of Linn and in the State of Iowa, have i-nvented certain-new and useful Improvem cuts in Balanced Valves and do hereby declare that the following is a full, clear, and exact description thereof,-reference being hadito the accompanying drawings, making a part of this specification, in which- Y V Figure 1 is a front elevation of my invention. Fig.2 is a side elevation. of the same.

Fig. 3 is a central longitudinal section. Fig. 4' is a transverse section on linelw w of Fig. 3.-

- duction of a cylindrical valve for use in admitting steam or compressed air to, and. permitting it to escape from, a cylinder, upon the sides and ends of which the pressure. of the same shall be so equalized as to enable said valve to move as easily when under pressure as when the same is removed; and it consists of the arrangement of the induction and eduction ports within the plug and its casing, substantially as and for the purpose hereinafter specified.

. In the annexed drawings, A represents the casing, having a general cylindrical form exteriorly, through the. center of which is formed an opening, that tapers'from one end of said casing to the other. Into the said tapering opening is fitted a plug, B, that corresponds therewith in size and shape, and is provided with a stem or spindle, G, that extends outward from the center of the largest end of said plug, and in a line with the same.

\ Fitted to and secured upon the largest end of the casingAis a head, D, provided with a sleeve, E, through the center of which is an opening corresponding in size and shape to the stem G, which opening receives said stem and furnishes a bearing for the same. The opposite end of said casing is closed by a second head, F, at the center of which is a threaded opening, f, for the reception of an induction-pipe. From the center of its smallest to a point near its largest end the .plugv Bis hollow, its interior communicating directly with the induction-opening f, while fromitslongitndinal center extend radially outwardtwo rectangular openings,b and b,

which have their longest axis in a line with said plug. Atopposite points upon the periphery of saijd plug are provided depressions b! and b that correspond in size'gandform' with;the openings band; b, and are provided withvpassages, which connect the same with'a I chamber, a, that is formed within the casing A,hetweenthe larger end of theplug B and head D. An enlargement, A, is formed upon one ejnd-ofthe casing A, and, extending from. the large end of said casing downward, is provided with a channel, a, that afi'ords comm unication between the chamber a and eductionport a." Opposite said eduction-port is formed incides with and covers the channel a, and

afi'ords free communication between the opposite end of the cylinder and the open air.

It will be seen that by rotating the plug B in either direction steam or compressed air will be admitted to and discharged from each end of the cylinderalternately. By admitting steam or compressed air at or through the' small end of the plug B its pressure will have a tendency to decrease the friction of said plug upon its seat, and consequently the power required to operate it, as well as the wear, will be materially lessened. As, however, the pressure, if excessive, might force the plug from its seat, or, if no pressure existed, said plug might wedge firmly into its seat, it has been found necessary to employ the following-described mechanism, in order that the relative position of said plug and easing may be insured. Upon the end of the sleeve Eopposite the head D is fastened a cross-head, E, through .point contained within a" corresponding recess that is formed within the end at the center of the spindle C, thus providing a means of adjustment whereby the plug may be held within its casing, and made to bear upon its seat with any desired pressure. An adjustable collar, L, is fitted upon and secured to the spindle immediately outside of the cross-head E, and, having its bearing upon the same, prevents the plug from being pressed too tight into its seat, and, in connection with the adjusting-screw L, enables said plug to be held in any desired position longitudinally. An arm, M, secured upon one of the studs H, central between the cross-head E and cross-bar K, together with the shaft'N and gearsN and N, completes the device, and furnishes a means for rotating the plug 01'. valve B.

A modified form of the plug and casing is shown in Fig. 5, the head D being omitted, and the plug in all respects the sameas shown in Figs. 3 and 4, except that its eductionpassages have an opening at the side and near the large end of the same, and correspond in size and position to similar openings provided in said casing, and which lead directly to the eduction-port a, It will be, seen that by admitting pressure through the small end of i the plug or valve it is relieved of all downward pressure, consequently great wear, friction, and loss of power, leaving to the mechanical device described the adjusting of said plug or valve to its seat.

Having thus fully set forth the nature and merits of my invention, what I claim as new is- The relative arrangement within the casing A and plug or valve B of the ports or openspectively, substantially as and for the purpose shown.

In testimony that I claim the foregoing I'- JOHN F. SWEET.

Witnesses:

GEO. S. PRINDLE, Jomv R. YOUNG. 

